| 摘要 |
A process for high hydroconversion of petroleum residua containing at least about 25 V % material boiling above 1000 DEG F. to produce lower boiling hydrocarbon liquid products and avoid undesirable precipitation of asphaltene compounds. In the process, the feedstock is at least about 50 percent catalytically hydroconverted to material boiling below 975 DEG F. and containing a mixture of gas and liquid fractions, after which the gas fraction is removed and the resulting liquid fractions is pressure-reduced and quenched to a temperature below about 775 DEG F. To avoid precipitation of asphaltene compounds which causes operational difficulties in the downstream equipment, the quench liquid used should have an API gravity not more than about 22 DEG API higher than the API gravity of the first pressure-reduced liquid fraction. The resulting liquid fraction is distilled to produce hydrocarbon liquid products, and a residual bottoms fraction is usually recycled to the catalytic reaction step to obtain increased percent conversion to lower boiling liquid products.
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